ES2307516T3 - PROCEDURE FOR THE PRODUCTION OF FURFURAL FROM RESIDUAL LIQUOR OF LIGNOSULFONATE. - Google Patents
PROCEDURE FOR THE PRODUCTION OF FURFURAL FROM RESIDUAL LIQUOR OF LIGNOSULFONATE. Download PDFInfo
- Publication number
- ES2307516T3 ES2307516T3 ES00940001T ES00940001T ES2307516T3 ES 2307516 T3 ES2307516 T3 ES 2307516T3 ES 00940001 T ES00940001 T ES 00940001T ES 00940001 T ES00940001 T ES 00940001T ES 2307516 T3 ES2307516 T3 ES 2307516T3
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- Prior art keywords
- liquor
- furfural
- heat source
- process according
- pentose
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- Expired - Lifetime
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D307/00—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom
- C07D307/02—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings
- C07D307/34—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having two or three double bonds between ring members or between ring members and non-ring members
- C07D307/38—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having two or three double bonds between ring members or between ring members and non-ring members with substituted hydrocarbon radicals attached to ring carbon atoms
- C07D307/40—Radicals substituted by oxygen atoms
- C07D307/46—Doubly bound oxygen atoms, or two oxygen atoms singly bound to the same carbon atom
- C07D307/48—Furfural
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Furan Compounds (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Paper (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Abstract
Description
Procedimiento para la producción de furfural a partir de licor residual de lignosulfonato.Procedure for the production of furfural a from residual lignosulfonate liquor.
La presente invención se refiere a la producción de furfural a partir de licor residual de lignosulfonato.The present invention relates to production of furfural from residual lignosulfonate liquor.
En función del tipo concreto de madera tratada, el proceso de producción de pulpa al sulfito produce un licor residual que puede contener entre un 0,9 y un 5,6 por cien de pentosa, lo que significa que tiene potencial para la elaboración de furfural.Depending on the specific type of treated wood, The sulphite pulp production process produces a liquor residual that can contain between 0.9 and 5.6 percent of pentosa, which means that it has potential for processing of furfural.
En el sistema convencional, el licor residual se espesa hasta conseguir un contenido en sólidos del cincuenta por cien o se seca totalmente, siendo vendido este licor o sólido como lignosulfonato. La pentosa es un componente indeseado de dicho licor.In the conventional system, the residual liquor is thickens until a solid content of fifty percent is achieved one hundred or completely dried, this liquor or solid being sold as lignosulfonate. The pentose is an unwanted component of said liqueur.
El licor residual del proceso se satura con sulfato cálcico, de modo que la elevada temperatura necesaria para la producción de furfural (preferentemente superior a 200 grados centígrado) acarrea la rápida y severa deposición de sulfato cálcico en las superficies calentadas, hecho que imposibilita el tratamiento continuo y prolongado.The residual process liquor is saturated with calcium sulfate, so that the high temperature needed to furfural production (preferably higher than 200 degrees centigrade) leads to rapid and severe sulfate deposition calcium on heated surfaces, which makes it impossible to continuous and prolonged treatment.
Si se evitan los intercambiadores de calor mediante la sustitución de la inyección directa del vapor, no es posible termodinámicamente mantener el licor en un estado de ebullición durante su tiempo de residencia porque las sustancias en solución elevan el punto de ebullición. Por lo tanto, a cualquier presión, el punto de ebullición del licor es superior al punto de condensación del vapor. Por consiguiente, el furfural producido a partir de la pentosa permanece temporalmente disuelto en la fase líquida en la cual, bajo el efecto catalítico de la acidez innata del licor, el furfural puede reaccionar con la pentosa, o el lignosulfonato, y con si mismo, incurriendo de este modo grandes pérdidas y en consecuencia escasos rendimientos.If heat exchangers are avoided by replacing direct steam injection, it is not thermodynamically possible to keep the liquor in a state of boil during your residence time because the substances in solution raise the boiling point. Therefore, to any pressure, the boiling point of the liquor is higher than the point of steam condensation Therefore, the furfural produced at starting from the pentose remains temporarily dissolved in the phase liquid in which, under the catalytic effect of innate acidity of the liquor, the furfural can react with the pentose, or the lignosulfonate, and with itself, thus incurring large losses and consequently low yields.
La US-A-2845441, FR-A-129139 y la EP-A-0124507 divulgan procesos para la producción del furfural a partir de licor residual de lignosulfonato, en los cuales un licor residual de lignosulfonato se calienta mediante la inyección directa de vapor y una fase de vapor con abundante furfural se condensa para producir furfural.US-A-2845441, FR-A-129139 and the EP-A-0124507 disclose processes for furfural production from residual liquor of lignosulfonate, in which a residual lignosulfonate liquor is heats by direct steam injection and a vapor phase with abundant furfural it condenses to produce furfural.
Constituye un objeto de la presente invención proporcionar un proceso para la producción eficaz de furfural a partir de licores de lignosulfonato, así como un aparato para realizar dicho proceso.It is an object of the present invention provide a process for the effective production of furfural to from lignosulfonate liquors, as well as an apparatus for Perform this process.
Por consiguiente, la presente invención proporciona un proceso para la elaboración de furfural a partir de licor residual de lignosulfonato que contiene pentosa, caracterizado en que el licor se mantiene en su punto de ebullición mediante una fuente de calor auxiliar y una descompresión controlada durante suficiente tiempo para que la pentosa se convierta en furfural, que se transfiere inmediatamente a la fase de vapor en cuanto se conforma, separando la fase de vapor con abundante furfural de la fase líquida sin que el furfural reaccione con la pentosa, el lignosulfonato o si mismo.Accordingly, the present invention provides a process for the development of furfural from residual lignosulfonate liquor containing pentose, characterized in which the liquor is kept at its boiling point by means of a auxiliary heat source and controlled decompression during enough time for the pentosa to become furfural, that is transferred immediately to the vapor phase as soon as conforms, separating the vapor phase with abundant furfural from the liquid phase without the furfural reacting with the pentose, the lignosulfonate or itself.
El reactor puede ser un reactor batch (por tandas) o continuo.The reactor can be a batch reactor (in batches) or continuous.
En un proceso preferente por tandas, se calienta un licor de lignosulfonato mediante vapor en un reactor que se despresuriza constantemente hasta presiones suficientes para mantener la ebullición del licor. El furfural que se conforma migra a la fase de vapor, se descarga con el condensado y se recupera.In a preferred batch process, it is heated a lignosulfonate liquor by steam in a reactor that is depressurizes constantly to sufficient pressures to keep boiling liquor. The furfural that conforms migrates to the vapor phase, it is discharged with the condensate and recovered.
En un proceso continuo de acuerdo con la
invención, el licor se hierve en un reactor continuo mediante una
fuente auxiliar de calor, descargándose el licor mientras el
furfural conformado se transfiere sustancialmente de forma
instantánea y completa a la fase gaseosa, saliendo del reactor, del
cual se sepa-
ra.In a continuous process according to the invention, the liquor is boiled in a continuous reactor by means of an auxiliary heat source, the liquor being discharged while the formed furfural is transferred substantially instantaneously and completely to the gas phase, leaving the reactor, of the which one knows
ra.
En una realización de la invención el licor se calienta en el reactor mediante una fuente auxiliar de calor, descargándose el licor, mientras el furfural conformado se transfiere sustancialmente de forma instantánea y completamente a la fase gaseosa, saliendo del reactor y del cual se separa.In one embodiment of the invention the liquor is heats in the reactor through an auxiliary heat source, discharging the liquor, while the furfural formed transfers substantially instantaneously and completely to the gas phase, leaving the reactor and from which it separates.
Preferentemente la fuente auxiliar de calor es aire caliente presurizado, que se puede introducir en el reactor a un nivel bajo. El aire se filtra por el licor en el reactor y, cediendo su calor, mantiene el licor en un estado de ebullición antes de salir del reactor.Preferably the auxiliary heat source is pressurized hot air, which can be introduced into the reactor at a low level The air is filtered by the liquor in the reactor and, giving up its heat, it keeps the liquor in a boiling state before leaving the reactor.
El licor se introduce en el reactor preferentemente a una temperatura de entre 180 y 280 grados centígrado.The liquor is introduced into the reactor preferably at a temperature between 180 and 280 degrees centigrade.
Se puede incorporar un circuito de control para mantener la presión en el cabezal del reactor a un valor ligeramente inferior a la presión del licor introducido. De este modo el vapor liberado que se produce provoca que el licor sufra una depresión menor a una temperatura inferior que obliga el furfural a pasar a la fase de vapor, mientras el aire caliente mantiene el licor en un estado de ebullición en todo el reactor. De este modo, el furfural producido a partir de la pentosa se vaporiza inmediata y completamente en cuanto se conforma y se une con el aire y una parte del agua vaporizada para formar una mezcla gaseosa con una mínima pérdida de rendimiento de furfural, porque las reacciones entre furfural y pentosa por una parte y con los lignosulfonatos por otra parte no pueden tener lugar porque la pentosa y los lignosulfonatos permanecen en solución. La reacción del furfural con si mismo es impedida por la ausencia de iones de hidrógeno en la fase de vapor.A control circuit can be incorporated to keep the pressure in the reactor head at a value slightly less than the pressure of the liquor introduced. In this way the steam released that occurs causes the liquor to suffer a depression lower than a lower temperature that forces the furfural to go to the vapor phase, while hot air keeps the liquor in a Boiling state throughout the reactor. In this way, the furfural produced from the pentose vaporizes immediately and completely as soon as it conforms and joins with the air and a part of the vaporized water to form a gaseous mixture with a minimal loss of furfural performance, because the reactions between furfural and pentose on the one hand and with lignosulfonates on another part cannot take place because the pentosa and the lignosulfonates remain in solution. The furfural reaction with itself is prevented by the absence of hydrogen ions in the steam phase
Se selecciona el tiempo de residencia en el reactor para que permita la conversión completa de la pentosa. No se requiere ninguna adición de ácido debido a la acidez innata del licor, que realiza una catálisis suficientemente fuerte.The residence time in the reactor to allow complete conversion of the pentose. Do not no acid addition is required due to the innate acidity of the liquor, which performs a sufficiently strong catalysis.
No hacen falta intercambiadores de calor, evitando de este modo los problemas asociados con el sulfato cálcico anteriormente comentados.You don't need heat exchangers, thus avoiding the problems associated with calcium sulfate previously commented.
En lugar de utilizar aire caliente como fuente auxiliar de calor, se puede emplear otros gases o mezclas de gases calientes (como un gas de combustión caliente) o el mercurio caliente, todos los cuales son fáciles de separar del licor al final de la reacción.Instead of using hot air as a source auxiliary heat, other gases or gas mixtures can be used hot (such as a hot flue gas) or mercury hot, all of which are easy to separate from the liquor at end of reaction
Se apreciará que se necesita un aporte de calor relativamente pequeño del agente térmico auxiliar, puesto que en esencia todo lo que se le exige es que vaporice el furfural producido. El bajo nivel de vaporización de furfural, sobre todo a temperaturas elevadas, significa que se necesita poco calor auxiliar.It will be appreciated that a heat input is needed relatively small auxiliary thermal agent, since in essence all that is required of you is to vaporize the furfural produced. The low level of furfural vaporization, especially at high temperatures, means that little heat is needed assistant.
El rendimiento de furfural incrementa con el aumento de la temperatura en el reactor puesto que las pérdidas por las reacciones con pentosa y lignosulfonatos así como los bisulfitos se suprimen a temperaturas más elevadas a causa del efecto de entropía en todas las reacciones de agregación.Furfural performance increases with the temperature increase in the reactor since losses due to reactions with pentose and lignosulfonates as well as bisulfites they are suppressed at higher temperatures because of the effect of entropy in all aggregation reactions.
Se apreciará que no es necesario añadir ácido alguno al licor para la catálisis, puesto que la acidez innata del licor efectúa una catálisis suficientemente fuerte.It will be appreciated that it is not necessary to add acid some to the liquor for catalysis, since the innate acidity of the Liquor performs a sufficiently strong catalysis.
El proceso de la invención se describe a continuación en relación con el organigrama que se acompaña.The process of the invention is described in then in relation to the accompanying organization chart.
Una bomba 1 alimenta un licor residual de lignosulfonato a través de un mezclador en línea 2, en el que la inyección de vapor lo calienta hasta una temperatura de entre 180 y 280 grados centígrado, aumentando la presión en consecuencia de este modo. Mediante una válvula de estrangulación 3, el licor se somete a una menor reducción de presión en el cabezal de un reactor de columna aislada térmicamente 4 y a continuación fluye hacia abajo para salir por la parte inferior por un ciclón 5 que produce una descompresión, un enfriamiento y un espesamiento.A pump 1 feeds a residual liquor of lignosulfonate through a line 2 mixer, in which the steam injection heats it to a temperature between 180 and 280 degrees Celsius, increasing the pressure as a result of this way. Using a throttle valve 3, the liquor is subject to a lower pressure reduction in the head of a reactor of thermally insulated column 4 and then flows down to exit at the bottom for a cyclone 5 that produces a decompression, cooling and thickening.
El aire comprimido se calienta eléctricamente en un intercambiador de calor y se alimenta por el circuito de control 7 al fondo del reactor. El aire caliente se cuela hacia arriba, cediendo su calor al licor y manteniendo el licor en un estado de ebullición de este modo antes de salir del cabezal del reactor por un circuito de control 8, un condensador 9 y una columna de absorción atmosférica 10 dotada de una bomba de circulación 11.The compressed air is electrically heated in a heat exchanger and is fed by the control circuit 7 at the bottom of the reactor. Hot air sneaks up, giving its heat to the liquor and keeping the liquor in a state of boil in this way before leaving the reactor head by a control circuit 8, a capacitor 9 and a column of atmospheric absorption 10 equipped with a circulation pump 11.
El circuito de control mantiene la presión en el cabezal del reactor a un valor ligeramente inferior a la presión de licor introducido. De este modo, al liberar vapor, el licor sufre una depresión menor hasta una temperatura ligeramente inferior, mientras el aire caliente mantiene el licor en un estado de ebullición en todo el reactor. El furfural producido se vaporiza inmediata y completamente y se une con el aire y el vapor para formar una mezcla gaseosa que se condensa en 9 y a continuación se recoge en el depósito 12. Las pequeñas cantidades de furfural arrastradas por el aire se recogen en la columna de absorción y se recogen en el depósito 12.The control circuit maintains the pressure in the reactor head at a value slightly below the pressure of liquor introduced. Thus, when releasing steam, the liquor suffers a minor depression to a slightly lower temperature, while the hot air keeps the liquor in a state of boiling throughout the reactor. The furfural produced is vaporized immediately and completely and binds with air and steam to form a gaseous mixture that condenses into 9 and then it collect in the tank 12. Small amounts of furfural airborne are collected in the absorption column and are collect in deposit 12.
La velocidad de entrada del licor y las dimensiones del reactor se establecen para corresponderse con un tiempo predeterminado de residencia del licor en el reactor.The liquor input speed and reactor dimensions are set to correspond with a default residence time of the liquor in the reactor.
Claims (8)
ebullición.2. Process according to claim 1, wherein the auxiliary heat source is pressurized hot air that is introduced into the reactor (4) at a low level, the introduction rate, temperature and pressure of the heat source being predetermined auxiliary to give up its heat during filtration through the liquor to keep the liquor in a state of
boiling.
centígrado.8. Process according to claim 1, wherein the auxiliary heat source is a gas at a temperature between 400 and 2000 degrees Celsius and preferably between 600 and 2000 degrees
centigrade.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19917178A DE19917178A1 (en) | 1999-04-16 | 1999-04-16 | Production of furfural from sulfite waste liquor involves heating by direct injection of steam, reaction by boiling under pressure, using easily separated ancillary, and complete vaporization by cooling and depressurization |
| DE19917178 | 1999-04-16 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| ES2307516T3 true ES2307516T3 (en) | 2008-12-01 |
Family
ID=7904762
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| ES00940001T Expired - Lifetime ES2307516T3 (en) | 1999-04-16 | 2000-04-14 | PROCEDURE FOR THE PRODUCTION OF FURFURAL FROM RESIDUAL LIQUOR OF LIGNOSULFONATE. |
Country Status (13)
| Country | Link |
|---|---|
| US (1) | US6642396B1 (en) |
| EP (1) | EP1171665B1 (en) |
| AT (1) | ATE404728T1 (en) |
| AU (1) | AU5499900A (en) |
| BR (1) | BR0009815B1 (en) |
| CA (1) | CA2370561C (en) |
| DE (2) | DE19917178A1 (en) |
| DK (1) | DK1171665T3 (en) |
| ES (1) | ES2307516T3 (en) |
| NO (1) | NO329326B1 (en) |
| PT (1) | PT1171665E (en) |
| WO (1) | WO2000063488A1 (en) |
| ZA (1) | ZA200108552B (en) |
Families Citing this family (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104193705B (en) | 2008-07-16 | 2017-09-01 | 瑞恩麦特克斯股份有限公司 | The method for extracting furfural and glucose from biomass using one or more supercritical fluids |
| US8546560B2 (en) | 2008-07-16 | 2013-10-01 | Renmatix, Inc. | Solvo-thermal hydrolysis of cellulose |
| US8119823B2 (en) * | 2008-07-16 | 2012-02-21 | Renmatix, Inc. | Solvo-thermal hydrolysis of xylose |
| US8282738B2 (en) * | 2008-07-16 | 2012-10-09 | Renmatix, Inc. | Solvo-thermal fractionation of biomass |
| CN105525043B (en) | 2010-01-19 | 2021-03-19 | 瑞恩麦特克斯股份有限公司 | Production of fermentable sugars and lignin from biomass using supercritical fluids |
| KR101192576B1 (en) * | 2010-11-30 | 2012-10-17 | 코오롱인더스트리 주식회사 | Continuous Preparation Method for Furfural from Xylose |
| CN102228896B (en) * | 2011-04-01 | 2013-05-22 | 山东万盛环保科技发展有限公司 | Furfural slag recycling device |
| US8801859B2 (en) | 2011-05-04 | 2014-08-12 | Renmatix, Inc. | Self-cleaning apparatus and method for thick slurry pressure control |
| JP5967730B2 (en) | 2011-05-04 | 2016-08-10 | レンマティックス, インコーポレイテッドRenmatix, Inc. | Production of lignin from lignocellulosic biomass |
| CN103619827B (en) * | 2011-06-22 | 2016-08-24 | 巴斯夫欧洲公司 | Make the method that the compositions of carbohydrate containing is dehydrated |
| US8759498B2 (en) | 2011-12-30 | 2014-06-24 | Renmatix, Inc. | Compositions comprising lignin |
| US9174909B2 (en) | 2012-02-02 | 2015-11-03 | Wisconsin Alumni Research Foundation | Two-stage, acid-catalyzed conversion of carbohydrates into levulinic acid |
| CN103193737B (en) * | 2013-03-29 | 2015-01-28 | 山东龙力生物科技股份有限公司 | Method for preparing furfural and co-producing lignin and cellulosic ethanol via plant material |
| SG10202003336XA (en) | 2014-09-26 | 2020-05-28 | Renmatix Inc | Cellulose-containing compositions and methods of making same |
| EP3626711A1 (en) * | 2018-09-24 | 2020-03-25 | Arbaflame Technology AS | Process for the production of furfural |
| CN116144038B (en) * | 2022-11-02 | 2024-05-07 | 华南理工大学 | Method for preparing furfural, lignin sulfonate and high degradable cellulose by integrated multi-process coupling |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1838109A (en) | 1930-06-06 | 1931-12-29 | Brown Co | Production of furfural |
| FR1129139A (en) | 1955-07-15 | 1957-01-16 | Paper mill waste liquor treatment process | |
| US2845441A (en) | 1955-11-16 | 1958-07-29 | Brown Co | Processes for production of furfural |
| AT367473B (en) | 1980-04-10 | 1982-07-12 | Kanzler Walter | METHOD FOR OBTAINING FURFUROL, FORMIC, ACETIC ACID FROM ACID HYDROLYSATES OF PLANTS |
| AT376717B (en) | 1983-05-02 | 1984-12-27 | Chemiefaser Lenzing Ag | METHOD FOR OBTAINING FURFUROL FROM ACID WATER DRAINAGE OF THE CELLULAR EQUIPMENT AND SYSTEM FOR IMPLEMENTING THE METHOD |
| US4533743A (en) * | 1983-12-16 | 1985-08-06 | Atlantic Richfield Company | Furfural process |
-
1999
- 1999-04-16 DE DE19917178A patent/DE19917178A1/en not_active Withdrawn
-
2000
- 2000-04-14 EP EP00940001A patent/EP1171665B1/en not_active Expired - Lifetime
- 2000-04-14 CA CA002370561A patent/CA2370561C/en not_active Expired - Fee Related
- 2000-04-14 PT PT00940001T patent/PT1171665E/en unknown
- 2000-04-14 DK DK00940001T patent/DK1171665T3/en active
- 2000-04-14 ES ES00940001T patent/ES2307516T3/en not_active Expired - Lifetime
- 2000-04-14 AU AU54999/00A patent/AU5499900A/en not_active Abandoned
- 2000-04-14 AT AT00940001T patent/ATE404728T1/en active
- 2000-04-14 BR BRPI0009815-9A patent/BR0009815B1/en not_active IP Right Cessation
- 2000-04-14 US US09/958,936 patent/US6642396B1/en not_active Expired - Fee Related
- 2000-04-14 DE DE60039860T patent/DE60039860D1/en not_active Expired - Lifetime
- 2000-04-14 WO PCT/ZA2000/000072 patent/WO2000063488A1/en active Search and Examination
-
2001
- 2001-10-16 NO NO20015031A patent/NO329326B1/en not_active IP Right Cessation
- 2001-10-18 ZA ZA200108552A patent/ZA200108552B/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| PT1171665E (en) | 2008-10-07 |
| EP1171665B1 (en) | 2008-08-13 |
| BR0009815A (en) | 2002-01-08 |
| CA2370561C (en) | 2009-06-16 |
| US6642396B1 (en) | 2003-11-04 |
| AU5499900A (en) | 2000-11-02 |
| CA2370561A1 (en) | 2000-10-26 |
| DK1171665T3 (en) | 2008-12-15 |
| ATE404728T1 (en) | 2008-08-15 |
| BR0009815B1 (en) | 2011-03-22 |
| WO2000063488A1 (en) | 2000-10-26 |
| DE60039860D1 (en) | 2008-09-25 |
| EP1171665A1 (en) | 2002-01-16 |
| NO20015031D0 (en) | 2001-10-16 |
| NO329326B1 (en) | 2010-09-27 |
| ZA200108552B (en) | 2002-08-22 |
| DE19917178A1 (en) | 2000-10-19 |
| NO20015031L (en) | 2001-12-11 |
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